This invention relates generally to switches for making and breaking electrical circuits. More particularly, this invention relates to switches for simultaneously making and breaking a redundant pair of circuits.
In some electrical circuits, it is desirable to provide redundantly switched circuits for control signals. The redundant circuit provides a greater degree of certainty that the switch was closed or opened intentionally and not by a failure mechanism, such as a short circuit.
One possible application of a redundant circuit is a speed control switch for a vehicle. The speed control switch provides, for example, control information to turn the speed control system on and off and to accelerate and decelerate the vehicle. It is important that in addition to providing redundant circuits, the switch positions also be tactile and that the switch mechanism itself be durable to withstand the physical stresses of use.
As is generally known, the vehicle manufacturing business is particularly competitive and highly automated. It is thus also desirable that the design for a redundant switch be inexpensive to produce and easily adapted to automated assembly.
Accordingly, one aspect of the present invention is to provide a tactile switch with redundant circuits.
Another aspect of the present invention is to provide a switch having redundant circuits that is durable and inexpensive to manufacture when compared with similar state of the art redundant switches.
In accordance with these aspects of the invention, an electrical switch is provided having redundant circuits. The switch has a pivotable plunger having an arcuate conductive bearing and a contact tip. The plunger bearing is electrically connected to the contact tip and is supported on a conductive substrate. When the plunger is pivoted from a first to a second position, the contact tip closes a first circuit between the substrate and a first contact and closes a second, redundant, circuit between the substrate and a second contact.
Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood however that the detailed description and specific examples, while indicating preferred embodiments of the invention, are intended for purposes of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.